any electricians on here ????

[Highbanked Hauler]

   My place has your basic 200 amp box on the house.   For emergency I bought a generator with  220 plug and my question is...  With the main breaker OFF can I run a 220 cord from the generator to the air compressor plug to power the breaker box ?  Obviously the generator won't power the whole house at one time but the HVAC unit and the water pump are  both 220  so would I be able to run one at a time or will my idea even work ??   Thanks,

[BLK 68 R/T]

I'm not an electrician. You could but you would only be powering up one side of the panel. Since the main power coming in is 2 hot lines and a ground, each hot line powers one side of the panel.

[birdsandbees]

No, he'd be powering both buss' as he feeds 220 back through a double pole breaker into the panel... the problem with feeding at a 220 plug for the compressor DOES IT HAVE A NEUTRAL wire. You'll need both hot and the neutral or you can't run any of your 120v items in the house.. ie lights.

Be ABSOLUTELY certain your main is pulled before generator start up and all your breakers are flipped off except the compressor line. Then select items carefully based on power draw that you want to run and flip their breakers on.

Failure to turn off that main could kill a hydro worker down the line as you'll be feeding 220 into the system.. through your transformer and put line voltage back in the "dead" service lines.   

[BLK 68 R/T]

Maybe my house just has an old panel in it? But the power coming in is split on each side of the panel. 220 breakers are just 2 lines off the same side of 110.

[birdsandbees]

No.. the double breakers may be/are on one side.. but every second "lug" that the breakers slip into comes from the other side. All doubles are feed from both buss's only way you'd get 220volts.

I'm not a licenced electrician, but I am an Electro-mechanical Engineer.

[BLK 68 R/T]

Ahh yes, the other leg goes to the other side. You are correct. For some reason I thought they both went to the same side on the double breakers. Thanks for straightening me out.

[RECHRGD]

I'm a retired electrical contractor.  Your power company will not be happy with you as there is the potential to back feed their lines and kill a lineman trying to restore power.  You can get a transfer switch set up that you can pick and choose what circuits that you want use (load shed).  Their not that expensive.  Be sure that the generator is sized properly for the loads you want to run.  Have a licensed electrician wire it up for you.  I've seen too many homeowners do some dangerous stuff....

[green69rt]

Just to throw my     Trying to hook a generator up to a house wiring system can be a little tricky but not much.  The big thing is you do NOT want power company hooked together thru your house.  

(Big explanation deleted)

I started to write a big explanation on how to install and operate a system but there are folks on here that could do that better than me.  I see they have already started.  Unless you're really after a safe and fail proof system ($$$) maybe do what I do.


There are wire sizes/lengths to consider, types of plugs, breaker sizes, the list goes on.  Best way to go, for the once or twice it might happen, is to just get some big extension cords and power the things you need individually.  Buy a small window AC that runs on  120 so you can sleep.  Fix your pump so it has a plug and just power the pump with an extension cord.  That's what I do and I'm an old Navy electrician.  Sometimes the simple solution is the best.  

[Highbanked Hauler]

I'm a retired electrical contractor.  Your power company will not be happy with you as there is the potential to back feed their lines and kill a lineman trying to restore power.  You can get a transfer switch set up that you can pick and choose what circuits that you want use (load shed).  Their not that expensive.  Be sure that the generator is sized properly for the loads you want to run.  Have a licensed electrician wire it up for you.  I've seen too many homeowners do some dangerous stuff....

    Believe me ,I don't have an ego to satisfy with some dumb idea nor do I want to risk anyone including myself. As I said in the original post, I know the generator won't power the whole house. I know you don't put a 30 amp draw on a 15 amp circuit.  I fully intend to get a switch put in. IF the main breaker is flipped OFF  how is there any other way that power can go back  out  of the house ?

[Mytur Binsdirti]

[RECHRGD]

I'm a retired electrical contractor.  Your power company will not be happy with you as there is the potential to back feed their lines and kill a lineman trying to restore power.  You can get a transfer switch set up that you can pick and choose what circuits that you want use (load shed).  Their not that expensive.  Be sure that the generator is sized properly for the loads you want to run.  Have a licensed electrician wire it up for you.  I've seen too many homeowners do some dangerous stuff....

    Beliesve me ,I don't have an ego to satisfy with some dumb idea nor do I want to risk anyone including myself. As I said in the original post, I know the generator won't power the whole house. I know you don't put a 30 amp draw on a 15 amp circuit.  I fully intend to get a switch put in. IF the main breaker is flipped OFF  how is there any other way that power can go back  out  of the house ?

With the main breaker in the open position the two hot wires will not feed back onto the line.  What if someone makes a mistake and closes the switch?  That's where the potential for an accident is.  The power company does not want to rely home owners doing everything right.  Many accidents occur every year.  I have a 9000 watt generator with a 30 amp four wire twist lock outlet on it.  I installed a GenTran six circuit transfer switch next to the house panel. I made up 10/4 cord that plugs into the GenTran from the generator.  I ran the 230 volt well pump circuit through it as well as four other 120 volt circuits.  If the power goes out I can have my water, freezers and some lights going in a matter of minutes.  When the power returns, you simply flip the GenTran switches to normal and unplug the generator.

[John_Kunkel]

I agree, use a six-circuit transfer switch. Here's a pic of my setup, 220 plug powers the transfer switch.

[RECHRGD]

LOL.  I have seen that before.  120 volt shower....

[RECHRGD]

I agree, use a six-circuit transfer switch. Here's a pic of my setup, 220 plug powers the transfer switch.

Thanks for posting the picture John.  I use a pad mostly and can't post pictures to this site from it.....

[NHCharger]

Al. My oldest son is a master electrician. If you want I can give you his number. He can walk you thru what you need.